Sterilizing method.



A JENSEN. l L STERILIZING METHOD. APPLICATIO FILED NOV. 9.1915 RNEWED JULYZ IQIB.

A. JENSEN.

y STERILIZING METHOD.

APPLICATION FILED Nov. s. |915. RENEwED IuLY 2.1918.

Paented Aug. 20, 1918..v

2 SHEETS-SHEET 2.

. to which the cans PATENT OFFICE.

AGE JENSEN, or LONG ISLAND CITY, NEW YORK.

STERILIZING METHOD.

Specification of Letters Patent.

\ Application led November 9, `1915, Serial No. 60,609. Renewed July 2,\191'8. Serial No. 243,089.

To, all whom t may concern:

Be it known that I, AAGE JENSEN, a eitizen of the United States, residing at Long Island City, in the county of Queens and State of New York, have invented a certain newand useful Sterilizing Method; and I do hereby declare the following` to be a full, clear, ,and exact description thereof, reference being had to the accompanying drawin s, forming part of this specification.

his invention relates generally to improvements in the sterilizing art. An example ofthe utilityof the invention is in the sterilizing of milkk cans after the contents have been removed and before the cans are refilled. Hence, for convenience, the following description will be conned to this particular use of the invention. y

A dirty milk can is a particularly favorable breeding ground for bacteria. This is due not only to the unsanitary conditions are subjected in shipment,

but also to the nature of the contents of the can, which, asis well known, form a medium whereln bacteria of every description develop ,withy amazing rapidity. When the isov cans have been emptied there is always a thin film or layer of milk adhering to the walls,-this film of milk frequently sour and alive with pathogenic bacteria. Consequently, to avoid pollution of the entire new supply of milk, itis absolutely essential that lthe can be thoroughly washed and presented for refilling in a sterile or rvery nearly sterile condition. v

The so-called sterilizing methods at present generally employed 1n dairies, are not conduciveto bringing about this most desirable condition. The common practice is .to rst immerse the cans in a sinka'nd scrub them to remove the dirt clinging to the outer walls of the cans and the layer of milk or congealed animal fat remaining in the cans. Then .the cans are steamed momentarily and set aslde forrefllhng. This practice is very objectionable for the washl water in the sink quickly becomes polluted from the dirty watel` flowing off the cans, so that often the whole Inumber of cans treated are affected. Again, the moisture remaining in the cans,

after the steaming process, permits the rapid `propagation of bacteria. after the cans have been a owed to cool to atmospheric temperature, and often results in the formation of metallic oxids .or other metal salts which react on kthe'milk subsequently placed in the 'the milk inthe cans and in addition cans, so as to give it a metallic flavor. vThis metallic flavor can not be removed' by pasteurizing and is a condition frequently found f Vmethod, or air heated to a sterilizing temperature, as disclosed in the present embodi` ment of the invention. During each step of the process absolute sterile conditions prevail and consequently practically ally of the germ life has been removed from the treated cans. Furthermore, the cans are perfectly dry when the sterilizing process is completed, so that there is no danger of the subsequent formation of metallic oXids. This prevents the imparting' of ametallic flavor to greatly increases the life of the cans themselves.

The accompanying drawings illustrate a preferred form of apparatus forl carrying out the improved method of thepresent invention. y

In the drawings,-

Iatented Aug. 20, 1918.

l'ns

Figure 1 is a plan view, partly in section,

Like characters of reference in the several v figures indicate the same parts.

Asshown, 'the cylindrlcal wall -1 of the casing surrounds an inner chamber 2. The

sides of said chamber may be inclosed by a' cylindrical wall 3 suitably insulated from the outer wall ofthe casing, as shown at 4. Upper and lower heads 5, 6 are provided respectively with flanges 5a, 6a, whereby they y may be secured to thev cylindrical wall 3 of the chamber 2. Said heads form the top and bottom inclosing walls of the chamber. Within the chamber 2 are tubes 7 extending all theway 'throu h the upper and lower heads 5, 6. l The tu vare open at both ends i ner. The spaces 7 nectedV with the intake of the blower12,'

- into throat 10 and having and may be secured totheheads 5, 6, by eX- panding their ends over the sides of suitable apertures in the heads, in the manner well known in the boiler construction art. Beneath lower head 6'of the chamber 2 is a bottom `plate 8 secured to the cylindrical wall 3 of said chamberin any suitable maninclosed by the several tubes 7 al'ord passages for the circulation of air and the spaces 2 between the tubes form a steam and condensation chamber. The space between lower-head 6 and bottom plate 8 forms an air chamber 8 which permits air to circulate down through some of the tubes and up the others, as will presentlyT appear.

he upper end of cylindrical wall 1 is closed by a cover plate 9 having a central throat or restricted. passage 10 provided with a cap 11.

Mounted above cap 11 is a blower 12 of suitable construction and the discharge endv of which communicates with a duct 13 extending through cap plate 11 its lower end Hared, as shown at 13. The flared portion 13 of ductf'13 rests on the upper head 5 of chamber 2. An air inlet pipe 14 is conf the duct. The air circulates down the cenwhich it passes up the the lcover plate9 is a sleeve r17.

traltubes into the air chamber 8, from outer tubes 7", upper ends of which are on. the outside-of lower flared end of the duct. tubes direct the air into the space 16 between duct 13 and the outer walls of the casing.

Revolubly. mounted around throat 10. of

.To reduce friction and allowthe sleeve to turn easily, anti-friction bearings 18 are provided b etween theflange 10 iof throat 10 and the lower end of the sleeve. Apacking 19 of suitable material is'also inserted in groove 19 of vflange '10 to eii'ect a tight seal and lubricate the parts during operation. Pros jecting from sleeve 17 is a seriesfof hollow arms 2O with the inner end of the duct21 in each arm communicatin with a corresponding discharge port 1 in the sleeve or table, one 22 l17. The outer end of each arm 20 is preferably forked, as shownin Fig. 1, whereby it is divided intotwo sections 20, 20"'. Each section is provided with a suitable bracket of which is adaptedto support the body of a milk can, and the other 22b of which supports the topof a milk can.

be driven by a pulley 12 to of the chamber.

' trols the' supply the i These condensation in geraete The discharge ends 21, 21b of the duct'21 1n arm 20' extend through the respective tables 22, 22", and form nozzles which direct `blasts ofair issuing from the space 16 into the can' body or top, as the case may be. Tables 22, 22b are provided withk ports 22A through which water and steam may be injected intfthe cans, at the desired time. The water out through drip ports or openings 22d in the tables. Throat 10 is provided with ay series ot ports 10b adapted to register with the ports 17 in sleeve 17. The number of ports 10", however, is less than the number of ports 17 in the sleeve, there being no port in the throat at thepoint where an arm 20 is in position for rinsing and steaming the can. Mounted within a small closed sleeve 23 in cap 11 is a downwardly spring pressed plunger 24'. The lower end of said plunger 24 is adapted to iit into recesses 25 in the upper Vace of rotary sleeve 17 when the sleeve ports 17 are `in registry with the ports 10 in throat 10. This construction provides a guide for informing the operator when the movable and stationary parts of the device are in operative relation to each other.

"Steam is supplied t'o the steam passages I 2 of chamber' 2, by a steam supply pipe 27, the upper end of which projects through cap 11 and is provided with a regulating valve 28 and a Huid 4pressure gage 29 for informing the operator of the amount of fluid pressure within the steam passages 2 end of the steam space or passages. 2 isl an outlet pipe 30 having a of steam to the vertical pipe 32. Vertical pipe) 32 is provided with branches or nozzles '33; and 34, one branch 33 of which is adapted to inject a column of iui'd through a port 22 in table 22, and the other branch 34 of which is adapted to inject a column of Huid through a similar port .in the other table 22". The iiow of iuid through each branch separately may be controlled by valves 35. Valve 31 is preferably arranged for operation by a foot pedal- 36 having operating connections 37 with the spindle of the valve. Byfregulating the size of the opening of the valve 31 the water of the steam space 2 may be kept at a given level without reducing the desired degree of pressure.

In operation, steam is -rst allowed to en# ter into the steam passages 2 by o ening regulating valve 28, the valve being le open until the desired degree of pressure 4is obtained. Water is condensed in the lower portion of the steam passages and is -under the pressure of the dryl steam-above. Fan 12 is then put in motion, thereby forcing air down through 'the central tubes 7 into the air chamber 8 up through the -outer tubes from the cans is allowed to run Connected with the lower` valve 31 which con- 7 5 and out the ducts 21 the arms'20, the

air emitting at the .discharge nozzles 21, 21b in a superheated condition. The body of a can to betreated is placed on a I table 22a in inverted position and the top of a canon `table 22h, which 'are first positioned 4over ing, the jet changes` automatically tok steam.

When the can has been steamed for a suicient time to destroy all the germ life, sleevev 17 is rotated to` a position whereina sleeve ort is in registry with a port in throat 10. he sterilized air now enters the canin large volumes, thereby'quickly absorbing all the moisture remaining from the rinsing and steaming processes. The can emerges from the treatment in a perfectly dry condition. The same operation is repeated until all of the cans have `:been treated. Revolving movement ofthe table carries the cans successively into positions wherein they aresubjected to the air blast, until the 'treated cansA are brought backto the operator who 'will take a position adjacent the Water and steam nozzles '33, 34. `The treated cans arevremoved and untreated cans placed on the l' tables. 4

I n actual practice, it is preferable tomain- Ktain approximately one .v5-hundred pounds pressure within. the steam 'passages `of the chamber 2./ With this pressure, the condensed water is injected r@into the cans at about 214 F., the water being absolutely temperatures f and sterile, because of its high temperature. vThe temperature of the air is always above 200 F., sometimes ranging as high as 240 F., so

that the air is itself at a sterilizingtemperature. c ItA is obvious, however, that the temperatures of the several sterilizing agents employed in'carrying out theprocess maybe increased by increasing the steam pressure within the'steam space 26. Much higher pressures -may be ernployed if desired. l

What is claimed isz' 1. A sterilizing method which consists yin rst 4washing the surface to be sterilized with water heated to a sterilizing temperature, 'then flooding the surface with steam until the surface is substantially sterile, and immediately thereafter, before corrosion of germ` life can take place, drying the wet sterile surface with ai'rheated to a sterilizing temperature.

2. A sterilizing method which consists 1n first washing the surface -to be sterilized with water, then flooding the surface with steam until the surfaceis substantially sterile, and. immediately thereafter dryin the wet sterile lsurface with previously sterilized` air. ;y

3. A sterilizing method which consists in `-lirs't washing thelsurface to be sterilized with water, then flooding the surface with steam until the surface'is substantially sterile, and immediately thereafter dryingthe wet sterile surface with' ilteredair heated to a sterilizing temperature. e JENSEN.

55 the wet sterile surface 'and propagation of 

